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1 Randolph Glacier Inventory Randolph Glacier Inventory – A Dataset of Global Glacier Outlines: Version 5.0 GLIMS Technical Report Arendt, A., A. Bliss, T. Bolch, J.G. Cogley, A.S. Gardner, J.-O. Hagen, R. Hock, M. Huss, G. Kaser, C. Kienholz, W.T. Pfeffer, G. Moholdt, F. Paul, V. Radić, L. Andreassen, S. Bajracharya, N.E. Barrand, M. Beedle, E. Berthier, R. Bhambri, I. Brown, E. Burgess, D. Burgess, F. Cawkwell, T. Chinn, L. Copland, B. Davies, H. De Angelis, E. Dolgova, L. Earl, K. Filbert, R. Forester, A.G. Fountain, H. Frey, B. Giffen, N. Glasser, W.Q. Guo, S. Gurney, W. Hagg, D. Hall, U.K. Haritashya, G. Hartmann, C. Helm, S. Herreid, I. Howat, G. Kapustin, T. Khromova, M. König, J. Kohler, D. Kriegel, S. Kutuzov, I. Lavrentiev, R. LeBris, S.Y. Liu, J. Lund, W. Manley, R. Marti, C. Mayer, E.S. Miles, X. Li, B. Menounos, A. Mercer, N. Mölg, P. Mool, G. Nosenko, A. Negrete, T. Nuimura, C. Nuth, R. Pettersson, A. Racoviteanu, R. Ranzi, P. Rastner, F. Rau, B. Raup, J. Rich, H. Rott, A. Sakai, C. Schneider, Y. Seliverstov, M. Sharp, O. Sigurðsson, C. Stokes, R.G. Way, R. Wheate, S. Winsvold, G. Wolken, F. Wyatt, N. Zheltyhina July 2015 1 Table of Contents 1 Introduction ..................................................................................................................................... 3 1.1 What is the RGI? ...................................................................................................................................... 3 1.2 Version History ....................................................................................................................................... 3 1.3 Data Distribution Policy ...................................................................................................................... 4 1.4 Data Sources ............................................................................................................................................. 5 1.5 Dataset Reference .................................................................................................................................. 5 2 Definitions of the RGI Regions ................................................................................................... 6 3 Data Description ............................................................................................................................. 9 3.1 Technical Specifications ................................................................................................................... 99 3.2 Data Fields and Hypsometry ........................................................................................................... 99 3.3 Glacier Delineation ............................................................................................................................. 14 3.4 Quality Control ..................................................................................................................................... 14 4 Revisions in RGI 5.0 ..................................................................................................................... 15 4.1 Overview ................................................................................................................................................ 15 4.2 Known Flaws ......................................................................................................................................... 15 5 Description of Data Compilation by Region ........................................................................ 16 5.1 REGION 1: Alaska ................................................................................................................................. 16 5.2 REGION 2: Western Canada and US ............................................................................................... 20 5.3 REGION 3: Arctic Canada North ...................................................................................................... 22 5.4 REGION 4: Arctic Canada South ...................................................................................................... 24 5.5 REGION 5: Greenland Periphery .................................................................................................... 26 5.6 REGION 6: Iceland ............................................................................................................................... 29 5.7 REGION 7: Svalbard ............................................................................................................................ 30 5.8 REGION 8: Scandinavia ...................................................................................................................... 33 5.9 REGION 9: Russian Arctic ................................................................................................................. 35 5.10 REGION 10: North Asia .................................................................................................................... 37 5.11 REGION 11: Central Europe ........................................................................................................... 39 5.12 REGION 12: Caucasus and Middle East ...................................................................................... 41 5.13 REGION 13: Central Asia ................................................................................................................. 43 5.14 REGION 14: South Asia West ......................................................................................................... 46 5.15 REGION 15: South Asia East .......................................................................................................... 48 5.16 REGION 16: Low Latitudes ............................................................................................................. 50 5.17 REGION 17: Southern Andes ......................................................................................................... 53 5.18 REGION 18: New Zealand ............................................................................................................... 56 5.19 REGION 19: Antarctic and Subantarctic .................................................................................... 57 6 References ...................................................................................................................................... 59 2 Randolph Glacier Inventory – A Dataset of Global Glacier Outlines: Version 5.0 GLIMS Technical Report July 2015 1 Introduction 1.1 What is the RGI? The Randolph Glacier Inventory (RGI) is a globally complete inventory of glacier outlines. It is supplemental to the Global Land Ice Measurements from Space initiative (GLIMS). Production of the RGI was motivated by the preparation of the Fifth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR5). The RGI was released initially with little documentation in view of the IPCC’s tight deadlines during 2012. More documentation is provided in the current version of this Technical Report. In due course the content of the RGI will be merged into the database of GLIMS. The RGI will, however, evolve into a downloadable subset of the extensive and diverse holdings of GLIMS, offering complete one-time coverage, version control and a standard set of attributes. The RGI was not designed for the measurement of glacier-by-glacier rates of area change, for which the greatest possible accuracy in dating, delineation and georeferencing is essential. Many RGI outlines pass this test, but in general completeness of coverage has had higher priority. Rather, the strength of the RGI lies in the capacity it offers for handling many glaciers at once, for example for estimating glacier volumes and rates of elevation change at regional and global scales and for simulating cryospheric responses to climatic forcing. In July 2014 development of the RGI became the responsibility of the Working Group on the Randolph Glacier Inventory and Infrastructure for Glacier Monitoring, a body of the International Association of Cryospheric Sciences. The members of the Working Group are listed in Table 1. 1.2 Version History Version 1.0 of the RGI was released in February 2012. It included a considerable number of unsubdivided ice bodies, which we refer to as glacier complexes, and a considerable number of nominal glaciers, which are glaciers for which only a location and an area are known; they are represented by circles of the appropriate area at the apppropriate location. An unofficial update of Version 1.0 was provided in April 2012 to replace several regions that had topology errors and repeated polygons. Version 2.0, released in June 2012, eliminated a number of flaws and provided a uniform set of attributes for each glacier. Several outlines were improved, and a number of outlines were added in previously omitted regions. Version 2.0 also added shapefiles for its first-order and second-order regions. Version 3.0 was an interim release representing the RGI as of 7 April 2013. It was the basis for the work of Gardner et al. (2013). The main improvements included identification of all tidewater basins, and separation of glacier complexes into glaciers in nearly all regions. Version 3.2, released in August 2013, included additional separation of glacier complexes into glaciers, and repairs of some geometry errors. It is the basis for the scientific description and analysis of the RGI by Pfeffer et al. (2014). 3 Version 4.0 was released on 1 December 2014. The most significant enhancement was the addition of
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